Rheostat



c. E. WARNER RHEOSTAT Filed Jan. 26, 1925 Patented Nov. 27, 1928. p v UNITED STATES PATENT OFFICE.

CHESTER E. WARNER, OF BERWYN, ILLINOIS, ASSIGNOR TO BENJAMIN ELECTRIC MFG. 00., OF CHICAGO, ILLINOIS, CORPORATION OFIIIIJINOIS- RHEOSTAT.

Application filed January My invention relates to rheostats, and more particularly to a rheostat to be mounted on a panel for controlling the current in the filament of an audion bulb.

[ One of the objects of my invention is to provide such a rheostat which can be easily mounted in a single opening in the panel.

and in which the resistance coil isin front of the panel so that the rear of the panel is left free and unobstructed.

A further object of my invention is to provide a rheostat which can be readily mounted in a single opening in a panel in which the resistance coil is carried by the controlling knob.

A further obj ect of my invention is to provide a rheostat in whichthe resistance coil is carried by the knob and which will be cheap in construction and durable and efiicient in use.

Further objects will appear from the description and claims,

In the drawings;

Figure 1 is a front view showing the rheoil stat mounted on the panel;

Fig. 2 is a rear view of the panel and rheostat mounting; I

Fig. 3 is a section on' the line 3-3 of Fig. 2;

M Figi 4 is a section on the line 4-4 of Fig.

Fig. 5 is a pbrspective view of a leaf spring acting between the knob and supporting stud.

5 Referring to the drawings in detail, the construction shown comprisesan insulating panel 10 having an opening 11 therethrough, a metal bushing 12 extending through this opening and provided with a wiring terminal 13 in the rear of the panel, a metal stud 14 extending through this bushing and insulated therefrom, and also provided with a wiring terminal 15 in the rear of the panehan insulating knob 16 rotatably mounted on the stud in front of the panel, a resistance coil 17 mounted on the knob and electrically connected with the stud, and a contact 18 mounted on the bushing and electrically connected therewith and engaging the resistance coil. A

The metal bushing is held on the insulating panel by a nut 19 which also serves to clamp the wiring terminal 13 in place. The metal stud 14 is held in "place in the bushing by having its end 20 riveted over, this rivet- 26, 1925. Serial No.4,636.

ing over also serving to hold the wiring terminal 15 in place. The metal stud 14 is insulated from the metal bushing 12 bymeans of an insulating sleeve 21, and an insulating washer22. The spring contact 18 so is held on the metal bushing 12 by the metal stud and is insulated from this stud by the sleeve referred to above and an' insulating washer 23. A metal washer 24 is provided between the insulating washer and the ens 65 larged shoulder 25 on the stud to provide an extended bearing surface. The insulating knob 16 which carries the resistance coil is rotatably mounted on the stud 14 by means of a circular disk 26 riveted onto the end of the stud and a plate 27 having a circular opening which has a working fit with the enlarged portion 25 of the stud and which is detachably secured to the insulating knob by means of a pair of screws 28 extending through openings in the plate and threaded into metal bushings 29 imbedded in the insulating knob 16. The plate 27 is held snugly up against the metal disk 26 by means of a bent leaf spring 30 seated in a recess 31 in the knob, the central portion 32 of this leaf spring bearing against the end of the stud and the end portions pressing against the knob.

The resistance coil 17 is seated in an annu- 86 lar recess in the knob and has one end secured underneath the head of one of the screws 28 so that the coil 17 is electrically connected with the stud 14 through the Plate 27. 90

In order to limit the rotation of the knob 16 it is provided with a stop shoulder 33 which engages the edge of the contact 18 (Fig. 4) to limit the movement of the knob.

The circuit is from the wiring terminal 13 through the bushing 12, spring Contact 18, resistance coil 17, plate 27 and stud 25 to the other wiring terminal 15.

It will be seen that a construction is thus provided by which the controlling knob also serves as an insulating support for the resistance coil and in which the rheostat can be mounted in a single opening in the panel, leaving the rear of the panel practically unobstructed.

I claim: I

1. A rheostat construction comprising a panel having an opening therethrough, a metal bushing extending through said opening, said bushing being provided with a wir- 110,

opening in a panel, said bushing being provided with a wiring terminal in the rear of the panel, a metal stud extending through said bushing and insulated therefrom, said stud being provided with a wiring terminal in the rear of the panel, an insulating knob rotatably mounted on said stud in front of said panel, a resistance coil mounted on said knob and electrically connected with said stud and a contact mounted on said bushing and electrically connected therewith and engaging said resistance coil.

3. A rheostat construction comprising a metal bushing for extending through the opening in a panel, a metal stud extending through said bushing and insulated therefrom, an insulating knob rotatably mounted on said stud in front of said panel, a resistance coil mounted on said knob and electrically connected with said stud and a contact mounted on said bushing and electrically connected therewith,and engaging said resistance coil.

4. A rheostat construction comprising a metal bushing for extending through the opening in a panel, a metal stud extending through said bushing and insulated therefrom, an insulating knob rotatably mounted on said stud in front of said panel, a resistance coil mounted on said knob, and means electrically connecting said stud and bushing through said coil.

5. A rheostat construction comprising a bushing for extending through the opening in a panel, a metal stud extending through said bushing and insulated therefrom, an insulating knob rotatably mounted on said stud in front of said panel, a resistance coil mounted on said knob, and means electrically connecting said stud and bushing through said coil, and means for mounting the knob on the stud comprising a plate mounted on the stud, a plate mounted on the knob and engaging the plate on the stud, and a spring holding one of said plates against the other.

6. A circuit controller construction comprising a metal bushing for extending through the opening in a panel, said bushing being provided with a wiring terminal in the rear of the panel, a metal stud extending through said bushing and insulated therefrom, said stud being provided with a Wiring terminal in the rear of the panel, two contact members mounted on said stud and bushing respectively, and a manually operable member rotatably mounted on said stud for controlling the circuit between said contacts.

In witness whereof, I have hereunto subscribed my name.

CHESTER E. WARNER 

